Terras mechanics reference the World of Ruin section of Final Fantasy 6, as she can Mill cards, and when she damages players, her owner can pay two to summon a 3 cost or less creature from the graveyard, emulating the party reforming in its second act
In the vast majority of games, the life that your opponent gains from you nuking their creatures with Swords to Plowshares will not amount to much, unless theyre playing a black deck with life-to-resource cards (watch out for Toxic Deluge or worse, Yawgmoths Bargain !) Swords to Plowshares isnt a particularly expensive card, and its very easy to find
Will of the Mardu deals damage to target creature equal to the number of creatures you control
Life from the Loam [Three Lands, Every Turn] Life from the Loam is one of the best MTG green spells if you want to turn lands into a renewable resource engine
Activate only if a player has one or fewer cards in hand and only as a sorcery